Hach DR/850 Procedures Manual page 170

FLUORIDE,
continued
9.
Place the prepared
sample into the cell
holder. Tightly cover the
sample cell with the
instrument cap.
Using AccuVac Ampuls
1.
Enter the stored
program number for
-
fluoride (F )- AccuVac
Ampuls.
Press:
PRGM
The display will show:
PRGM ?
10.
Press:
READ
The cursor will move to
the right, then the result
in mg/L fluoride will be
displayed.
Note: Use of the Standard
Adjust feature with each
new lot of reagent is highly
recommended. See
Accuracy Check following
these steps.
2.
Press:
28 ENTER
The display will show
mg/L, F and the
ZERO icon.
3.
Collect at least 40
mL of sample in a
50-mL beaker. Pour at
least 40 mL of
deionized water into a
second beaker.
170
4.
Fill a SPADNS
Fluoride Reagent
AccuVac Ampul with
sample by breaking the
tip on the bottom of the
beaker. Fill a second
AccuVac Ampul with
deionized water
(the blank).
Note: Keep the tip
immersed while the ampule
fills completely.